We present the first molecular level characterization of natural petroleum seeps and asphalt volcanoes discovered off the coast of Southern California by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Although natural petroleum seeps to the ocean account for nearly half of all input, only a small number of seafloor features associated with active seepage have been characterized. Here, we describe the detailed, molecular-level characterization of polar species and condensed aromatic structures petroporphyrins accessible only by ultrahigh resolution FT-ICR mass spectrometry.  Collectively, the results reveal an immense compositional diversity of polar species, condensed aromatic structures, and vanadyl and nickel porphyrins that rivals heavy oil and refinery residues in complexity. Comparison of the molecular composition between petroleum seeps and hydrocarbon material deposited in asphalt volcanoes reveals the inherent geochemical complexity associated with these structures. Biodegradation that occurs at the seafloor (anoxic) as compared to surface degradation will also be discussed, as well as biodegradation molecular level transformations associated with two recent oil spills.

Biodegradation at the seafloor: Ultrahigh resolution FT-ICR mass spectral characterization of natural petroleum seeps in the Gulf of Mexico

245th National Meeting (2013)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.